DESCRIPTION: This is a FIRST application for a randomized trial of churches in East Baltimore testing a self-help, minimal intervention compared with an intensive physical activity intervention. The investigator will evaluate the effectiveness of a six-month moderate-intensity physical activity intervention for increasing total daily energy expenditure of sedentary African-American women who are between the age of 50 and 70 years. The goal of the intervention is to increase total daily energy expenditure by 150 kilocalories per day and time spent in moderate-intensity physical activity by 30 minutes per day. Effects of increased physical activity on selected cardiovascular risk factors (e.g., peak oxygen uptake, blood pressure, HDL cholesterol, serum insulin and plasma glucose) will also be determined. Six churches will be randomized into intensive or minimal intervention status, and 33 women per church will be recruited, for a total of 100 women in each condition. The physical activity intervention will consist of twice-weekly aerobics classes conducted at the churches and additional group-and home-based programming. Volunteer lay leaders will be trained as neighborhood exercise specialists to supplement certified aerobics instructors in conducting the intervention. The proposed study will fill an existing gap by examining how a culturally sensitive physical activity intervention conducted in a community setting is associated with increased daily energy expenditure in African American women -- a group of women who are sedentary and at risk for health problems for which regular physical activity can provide benefits. Also, a great deal should be learned about assessment of physical activity in this subpopulation as well.